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                交与并                </h1>
                <p>时间限制：10s&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;  空间限制：128MB</p>			</div>
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                                <h3>题目描述</h3><p><p class="MsoNormal" style="margin: 0cm 0cm 0pt"><b style="mso-bidi-font-weight: normal"><span lang="EN-US" style="font-size: 12pt; font-family: 幼圆; mso-hansi-font-family: 宋体"><span style="mso-tab-count: 1">&nbsp;&nbsp; </span><span style="mso-spacerun: yes">&nbsp;</span></span></b><span style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt"><font size="3">对于一个区间集合<span lang="EN-US">{A1,A2</span>&hellip;&hellip;<span lang="EN-US">AK}(K&gt;1</span>，<span lang="EN-US">Ai&lt;&gt;Aj{i&lt;&gt;j})</span>，我们定义其权值</font><span lang="EN-US"><br />
<font size="3"><span style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span><b style="mso-bidi-font-weight: normal">W=|A1</b></font></span><font size="3"><b style="mso-bidi-font-weight: normal">&cup;<span lang="EN-US">A2</span>&cup;&hellip;&hellip;&cup;<span lang="EN-US">AK|*|A1</span>&cap;<span lang="EN-US">A2</span>&cap;&hellip;&hellip;<span lang="EN-US">AK|</span></b><span lang="EN-US"><o:p></o:p></span></font></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt"><font size="3"><b style="mso-bidi-font-weight: normal"><span lang="EN-US" style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt"><span style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp;&nbsp; </span></span></b><span style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt">当然，如果这些区间没有交集则权值为<span lang="EN-US">0</span>。<b style="mso-bidi-font-weight: normal"><span lang="EN-US"><o:p></o:p></span></b></span></font></p>
<p></p></p><hr/><h3>输入格式</h3><p><p class="MsoNormal" align="left" style="margin: 0cm 0cm 0pt; text-align: left; mso-layout-grid-align: none"><b style="mso-bidi-font-weight: normal"><span lang="EN-US" style="font-size: 12pt; color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H"><span style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;</span><span style="mso-spacerun: yes">&nbsp;</span></span></b><span style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt"><font size="3">给你<span lang="EN-US">N</span>个各不相同的区间，请你从中找出若干个区间使其权值最大。<span lang="EN-US"><o:p></o:p></span></font></span></p>
<p class="MsoNormal" align="left" style="margin: 0cm 0cm 0pt; text-align: left; mso-layout-grid-align: none"><span lang="EN-US" style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt"><o:p><font size="3">&nbsp;</font></o:p></span></p>
<p class="MsoNormal" align="left" style="margin: 0cm 0cm 0pt; text-indent: 21pt; text-align: left; mso-layout-grid-align: none"><font size="3"><span lang="EN-US" style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt"><span style="mso-spacerun: yes">&nbsp;</span></span><span style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt">第一行<span lang="EN-US">N<o:p></o:p></span></span></font></p>
<p class="MsoNormal" align="left" style="margin: 0cm 0cm 0pt; text-indent: 21pt; text-align: left; mso-layout-grid-align: none"><font size="3"><span lang="EN-US" style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt"><span style="mso-spacerun: yes">&nbsp;</span></span><span style="color: black; font-family: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: SimSun-Identity-H; mso-bidi-font-size: 10.5pt">接下来<span lang="EN-US">N</span>行 <span lang="EN-US">l r(1&lt;=l&lt;r&lt;=10^6)</span></span></font></p></p><hr/><h3>输出格式</h3><p><p>&nbsp;&nbsp;&nbsp; 最大权值<br />
</p></p><hr/><h3>样例输入</h3><pre> 4

 1 6

 4 8

 2 7

 3 5


   </pre><hr/><h3>样例输出</h3><pre> 24

 
样例注释:选择第1个和第3个区间,交为(2,6),并为(1,7),
权值为4*6=24.
</pre><hr/><h3>提示</h3><p><p>100%&nbsp; 1&lt;N&lt;=10^6<br />
</p></p><hr/><h3>题目来源</h3><p>没有写明来源</p>
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